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There is growing evidence of the importance of miRNAs for intestinal functional properties and nutritional uptake. Comparative miRNAs profiles of the jejunal mucosa were established against two genetic backgrounds (Lohmann Brown-Classic (LB) and Lohmann LSL-Classic (LSL), which are similar in egg production but differ in physiological traits including mineral utilization, along the production periods of laying hens. The target genes of miRNAs higher expressed in LB vs. LSL (miR-126-3p, miR-214, miR-24-3p, miR-726-5p, miR-29b-3p) were enriched for energy pathways at all stages. The target genes of the miRNAs higher in LSL (miR-1788-5p, miR-103-3p, miR-22-5p, miR-221-3p, miR-375) were more enriched for immune and the bone signalling pathways . The most prominent expression differences were between 16 and 24 weeks of age before and after onset of laying. Our results evidence central roles of intestinal miRNAs as regulators of gene expression, influencing intestinal homeostasis and adaptation to environment in different strains and production phases.

The objective of this study was to compare 2 laying hen strains in 5 production periods regarding phytase activity, phytate (InsP6) degradation, and myo-inositol (MI) release in the digestive tract and phosphorus (P) and calcium (Ca) utilization. One offspring of 10 nonrelated roosters per strain (Lohmann Brown-classic (LB) or Lohmann LSL-classic (LSL)) was placed in one of 20 metabolic units in a completely randomized block design in week 8, 14, 22, 28, and 58 of life. All hens were fed the same corn and soybean meal–based diet at one time, but the diet composition was adjusted to the requirements in the respective period. For 4 consecutive days, excreta were collected quantitatively at 24-hour intervals. In week 10, 16, 24, 30, and 60, the blood plasma, digesta of crop, gizzard, jejunum, ileum, and ceca, and mucosa of the jejunum was collected. The concentration of inorganic P in the blood plasma was higher in LB than in LSL hens (P = 0.026). Plasma Ca concentrations increased with each period (P

Mitochondria are key intracellular targets of hypoxia-reoxygenation (H/R) stress due to their central role in generation of ATP and reactive oxygen species (ROS). Intertidal oysters Crassostrea gigas are adapted to frequent H/R cycles and maintain aerobic function despite frequent oxygen fluctuations. To gain insight into the molecular mechanisms of H/R tolerance, we assessed changes in mitochondrial respiration and (phospho)proteome of C. gigas during hypoxia and recovery. Oyster mitochondria maintained OXPHOS capacity despite a decline in cytochrome c oxidase activity during H/R stress. Rearrangements of the mitochondrial proteome during H/R stress involved upregulation of mitochondrial electron transport system and iron-binding proteins, and suppression of the pathways that channel electrons to ubiquinone, possibly as a mechanism to limit ROS production. H/R stress led to upregulation of a mitophagic activator PGAM5 and dephosphorylation of metalloendopeptidase OMA1, indicating stimulation of mitochondrial quality control mechanisms. Changes in abundance and phosphorylation levels of key proteins involved in mitochondrial protein homeostasis indicate suppression of protein synthesis during hypoxia, likely as an energy-saving mechanism, and its subsequent reactivation during reoxygenation. Thus, shifts in the mitochondrial (phospho-)proteome might play an important role in H/R stress resistance of oysters ensuring mitochondrial integrity and function during oxygen fluctuations. SIGNIFICANCE: Hypoxia-reoxygenation (H/R) stress elicits shifts in proteome and phosphoproteome of mitochondria in a hypoxia-tolerant model bivalve, oyster Crassostrea gigas, upregulating electron transport system, limiting electron flow to ubiquinone and activating mitochondrial quality control and protein homeostasis mechanisms. These findings provide insights into the potential role of proteomic shifts in adaptive response to H/R stress and serve as an important benchmark to understand the mechanisms of mitochondrial sensitivity to hypoxia and reoxygenation.

Daily and seasonal temperature fluctuations are inevitable due to climate change, which highlights the importance of studying the detrimental effects of temperature fluctuations on the health, productivity, and product quality of farm animals. Muscle membrane composition and the molecular signals are vital for muscle cell differentiation and muscle growth, but their response to temperature stress is not well characterized. Temperature changes can lead to modification of membrane components of the cell, which may affect its surroundings and intracellular signaling pathways. Using C2C12 myoblast cells as a model of skeletal muscle development, this study was designed to investigate the effects of high temperature (39 °C and 41 °C) and low temperature (35 °C) on molecular pathways in the cells as well as the cell membrane fatty acid composition. Our results show that several genes were differentially expressed in C2C12 cells cultured under heat or cold stress, and these genes were enriched important KEGG pathways including PI3K-Akt signaling pathway, lysosome and HIF- signaling pathway, Wnt signaling pathway and AMPK signaling pathway. Our analysis further reveals that several membrane transporters and genes involved in lipid metabolism and fatty acid elongation were also differentially expressed in C2C12 cells cultured under high or low temperature. Additionally, temperature stress shifts the fatty acid composition in the cell membranes, including the proportion of saturated, monounsaturated and polyunsaturated fatty acids. This study revealed an interference between fatty acid composition in the membranes and changing molecular pathways including lipid metabolism and fatty acids elongation mediated under thermal stress. These findings will reinforce a better understanding of the adaptive mechanisms in skeletal muscle under temperature stress.

Local cultivars of comfrey (Symphytum spp.) have been used to cover protein and mineral requirements of farm animals in low-input systems. Due to its known health-promoting (e.g. allantoin), but also anti-nutritive ingredients (e.g. pyrrolizidine alkaloids), multidisciplinary approaches are essential in order to quantify the nutritional value and the potential of its use in poultry and farm animals in terms of meeting animal needs, using local resources as well as remediating over-fertilized soils. Focusing on animal effects, here one-day old sexed Cobb500 broiler chickens were subjected to either a standard control diet or a standard diet supplemented with 4% dried comfrey leaves for 32 days. Performance traits indicate good acceptance of supplementation with comfrey leaves. Parameters for liver function, mineral homeostasis, bone mineral density as well as intestinal microanatomy revealed no signs of impairment. Quantified pyrrolizidine alkaloids were below the detection limit in liver and breast muscle (

Stress response and coping behavior in pigs are largely shaped by hypothalamic-pituitary-adrenal axis and sympatho-adrenomedullary system action. However, the dynamic interaction between amygdala and hippocampus crucially modulates the behavioral response towards significant emotional events. While this functional relationship is well documented, the molecular underpinnings still remain insufficiently understood. Our study used transcriptome profiling of porcine amygdala and hippocampus to identify molecular pathways that are differentially activated depending on the haplotype of a significantly coping behavior-associated region on pig chromosome 12 (SSC12). The pigs were classified into two groups based on the haplotype information of this QTL-region discovered in our previous genome-wide association study. Ten each of high- (HR) and low- (LR) reactive pigs (n = 20) were selected for differential gene expression analysis and weighted gene co-expression analysis with subsequent pathway analysis. Differentially expressed genes identified in the amygdala include SELL, CXCR7 and NTS, while TRAF3, PTGS2 and CFI were detected in the hippocampus indicating a role of neuroinflammation and immunological processes. Pathway analysis revealed IL-8 signaling, NF-κB signaling, glutamate and GABA metabolism, glucocorticoid receptor signaling and chemokine signaling in the amygdala and ephrin receptor signaling, as well as NF-κB signaling in the hippocampus. We discovered candidate genes in regions detected by genome-wide association study including ARRB2, ADRBK2, THRB, NEK7 and ACVR2B, which relate to dopaminergic and other monoaminergic neurotransmitter systems, neuroimmunomodulation, neuroinflammation and GABA-ergic neurotransmission. These findings provide insights into the molecular underpinning of divergent coping behavior and associated haplotypes in limbic forebrain system in pig.

Glucocorticoid receptor (GR) is a transcription factor activated by circulating glucocorticoids and mediates their effects on various biological functions in the body. The final cellular activity of GR is modulated by alternative splicing and cell-type specific expression of its encoding gene NR3C1. To enhance the current knowledge of alternative processing of NR3C1 in mammalian species and to facilitate future studies of its regulation in the pig we explored here structural diversity, and tissue-specific distribution of transcript variants of the porcine NR3C1, and the correlation between usage of alternative promoters and alternative splicing. We experimentally identified ten alternatively used untranslated first exons (1A, 1B, 1C, 1D, 1E, 1F, 1G, 1H, 1H2 and 1J) and four transcript variants encoding different GR subtypes (GR-alpha, GR-beta, GR-P and GR-gamma). Expression profiling of nine most important target tissues of glucocorticoids revealed that the promoter of exon 1C drives constitutive expression of the predominant GR-alpha subtype. We found compelling evidence that the occurrence of exon 1D influences abundance of the GR-P splice variant, while both seems to play an important role in regulating GR activity in neuroendocrine tissues. Exons 1A and 1B in turn appear to be important for the regulation of the expression of the porcine NR3C1 in liver and spleen. Our results demonstrate that tissue-specific actions of GR depend on the usage of alternative promoter regions that favour the processing of certain GR subtypes.

The present study was conducted to test the hypothesis whether prion protein gene ( PRNP ) associated scrapie susceptibility is connected with physiological changes in tissue involved in pathogen uptake, migration and propagation. Jejunum, ileal Peyer's patches, retropharyngeal lymph nodes, brain stem and liver of healthy and non scrapie-infected sheep with PRNP genotypes representing the scrapie risk class R1 (scrapie-resistant) and R5 (scrapie-susceptible), respectively, were comparatively analysed by microarray technology and quantitative reverse transcriptase polymerase chain reaction (RT qPCR). Significantly higher expression levels of genes involved in immune response and cell communication pathways in retropharyngeal lymph nodes of R1 sheep in comparison with R5 animals strongly suggest PRNP associated physiological processes with impact as an early barrier in pathogen defence. Equal expression patterns in brain stem suggest no physiological differences in brain of healthy R1 and R5 animals. In addition, similar expression pattern in liver indicates that there are no transcriptional differences in genes of the hepatic energy metabolism between animals of scrapie classes R1 and R5.

Maternal nutrition during gestation has important effects on offspring gene expression mediated by DNA methylation. In order to evaluate the effect of restricted and excess protein intake during gestation, hepatic gene expression and DNA methylation of key metabolic genes NR3C1, PPARα, HMGCR, PGC1α, INSR and CYP2C34 were investigated. Liver samples of German Landrace offspring were collected at Gestational Day 95, at birth, at weaning and from finisher pigs. Gene expression in foetal liver revealed significant differences between the control group (CO) and the low-protein group (LP) in HMGCR (P